Wire EDM Vibration Control Using Compressive Position Reconstruction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wire EDMs face challenges in accurately estimating wire vibration due to disturbances and different forces during machining, leading to inaccurate control and deterioration of workpiece quality.
Innovation Solution
A wire EDM system utilizing a light source to illuminate the wire electrode with an encoded illumination pattern, a camera to acquire images, and a processor to reconstruct wire positions using compressive sensing with sparse reconstruction techniques, enabling precise control of the machining process without the need for high-speed cameras.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional optical methods are used to detect wire vibration, then small vibrations can be detected, but the estimation results are inaccurate for controlling the wire EDM
Solution Approach 1:
The patent transitions from one-dimensional sensor detection to two-dimensional camera imaging to capture wire position. The camera records the wire's shadow or image on a two-dimensional plane, enabling more comprehensive vibration analysis in multiple directions simultaneously, thus resolving the contradiction between detecting small vibrations and achieving accurate cutting control.
Solution Approach 2:
The patent replaces conventional mechanical/optical sensors with a vision-based measurement system using camera imaging. This substitution allows non-contact, full-field measurement of wire position and vibration, providing more accurate data for controlling the wire EDM while avoiding the limitations of traditional sensor-based methods.
2Measurement precision
If high-speed cameras are used to capture wire positions, then accurate vibration estimation is achieved, but equipment cost increases significantly
Solution Approach 1:
The patent uses periodic pulsed illumination instead of continuous high-speed imaging. By illuminating the wire with periodic light pulses synchronized with the wire vibration frequency, the system can capture critical vibration information at key moments, achieving accurate vibration estimation with a standard-speed camera and reducing equipment costs.
Solution Approach 2:
The patent creates a two-dimensional shadow or image copy of the wire's position and vibration on the camera sensor. This optical copying approach allows standard cameras to capture vibration information that would otherwise require expensive high-speed imaging systems, reducing equipment complexity while maintaining measurement precision.
3Manufacturing precision
If the wire is kept stationary to reduce vibration, then cutting precision improves, but machining productivity decreases
Solution Approach 1:
The patent implements a feedback control system that continuously monitors wire position and vibration using camera imaging. The system provides real-time feedback on wire deviation and adjusts machining parameters or wire tension dynamically, allowing the wire to maintain cutting precision even during high-speed operation, thus resolving the contradiction between accuracy and productivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach allows for accurate estimation of wire electrode positions and vibrations, reducing the risk of wire breakage and enhancing the precision of cuts, particularly in skim cutting, while minimizing equipment costs.
Implementation Method 1
one or more conventional methods utilize optics to focus a reflection of light to a one-dimensional sensor detecting an oscillation of the wire
Implementation Method 2
reconstructing positions of at least a segment of the wire electrode at a reconstruction rate greater than an acquisition rate of the camera by utilization of compressive sensing with sparse reconstruction technique
Implementation Method 3
Material is removed from the metal workpiece by a series of rapidly recurring current discharges between two electrodes
Implementation Method 4
an intensity of an electric field in a volume between the wire and the workpiece becomes greater, thereby causing a dielectric breakdown of the dielectric liquid, that leads to production of an electric arc
Data Source
AI summary
Embodiments of the present disclosure provide a wire electric discharge machine (EDM) including a delivery system with one or combination of a wire electrode and a workpiece for delivering the wire electrode and the workpiece into proximity of each other and an energy source for creating electric discharge between the wire electrode and the workpiece. The wire EDM includes a wire electrode position measurement unit including light source to illuminate the wire electrode with encoded illumination pattern and a camera for acquiring a set of images of the wire electrode illuminated by the encoded illumination pattern. The wire EDM includes a processor to reconstruct positions of a segment of the wire electrode at a reconstruction rate greater than an acquisition rate of the camera by utilization of compressive sensing with sparse reconstruction technique and a controller to control the delivery system and the energy source based on the reconstructed positions.